As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PRE-FLIGHT OBSERVED OVERHEAD AMBER, ELEC LIGHT ILLUMINATED. ACFT GROUNDED. BITE CHECKED P5-13 FAULTS AUX BATTERY CHARGER FOUND C/B E3, ON P91 OUT. R & R AUXILIARY BATTERY CHARGER IAW AMM 24-31-31-000-801/24-31-31-400-801. OPS CK GOOD.